pgsql: vacuumlo: Use a cursor to limit client-side memory usage.

vacuumlo: Use a cursor to limit client-side memory usage.

This prevents the client from gobbling up too much memory when the
number of large objects to be removed is very large.

Andrew Dunstan, reviewed by Josh Kupershmidt

Branch
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master

Details
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http://git.postgresql.org/pg/commitdiff/67ccbb080d87a5379dffc1cdff046c4caf534a6c

Modified Files
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contrib/vacuumlo/vacuumlo.c |  111 +++++++++++++++++++++++++++----------------
1 file changed, 69 insertions(+), 42 deletions(-)